Combine levels across several LinkMaps in a MultiFactor

Generates a new LinkMap object by merging levels by name, separated by the plus (+) sign. See examples.

Arguments

x

a MultiFactor

.path

a formula of length 2 with with levels to be merged separated by the plus (+) sign. Optionally, a list with two character vectors, signifying the variables to be combined at the left and right hand side, respectively.

...

Additional arguments (unused.)

out.format

Character scalar. One of 'LinkMap', 'matrix'.

Value

a LinkMap or sparse Matrix.

Examples

# Only necessary in example code
require(utils)

x <- randomMultiFactor()
# Merge variables with "+" operator, new names get concatenated with ".":
stack(x, b ~ c + d)
#> A MultiFactor::LinkMap data.frame S7_object: 81 rows.
#>        b   c.d
#> 1  b_003 c_001
#> 2  b_009 c_001
#> 3  b_003 c_002
#> 4  b_004 c_002
#> 5  b_006 c_002
#> 6  b_010 c_002
#> 7  b_007 c_004
#> 8  b_001 c_005
#> 9  b_003 c_005
#> 10 b_005 c_005
#>  + 71 more rows. Use `print(n = ...)` to see more rows.
#> 
#> @ levels:   2 variables: 
#>  $ b   : 10 Levels: b_001 b_002 ... b_010 
#>  $ c.d : 20 Levels: c_001 c_002 ... d_010